Sunday, March 16, 2014

In last blog, I discuss on BOM concept. There I mention
various Bill of Material aspects in various stage of product and their
dependency. It is interesting to discuss on BOM lifecycle and its evolution
from conceptual stage to full fledge manufactured product to maintenance. In
this blog I will explain through life cycle of BOM across the product life
cycle done as in house development. The BOM lifecycle can varies based on overall process of company for example some company might only manufacture as order hence they As Build design BOM and they directly CREATE Manufacturing BOM from it.

Concept BOM

As the product is visualize based on input from various
source like client, sales, technology advancement etc, the Bill of Material creation
started. The concept BOM can be created
either from scratch or derived from existing BOM. This BOM can be generated
from CAD if the product is more engineering rich product or non CAD if it more features
bases products where CAD might be subset of overall product. This BOM are used
for proof of concept and goes through various iteration for design feasibility,
cost consideration, compliances etc. Once concept phase is completed and
decided on basic design and feature of Products, it moves product design.

Design BOM

Design BOM usually driven from concept phase. Design BOM can
be derived from concept BOM or can be created completely new based on maturity
of concept BOM. BOM are either created Top Down or bottom up. Top down BOM as
name suggested design by defined from top like modules or assembly level and
defined detail part in advance stage of product development, where as bottom up
come to picture where design is done from parts or component level. Usually functional
driven product development is done top down where systems or subsystems are
defined first and then boiled down to detail design of Bill of Material. Complex
product is usually designed through Top down design like Space Craft, heavy
automatic machine etc. Teamcenter has Modular BOM functionality to support Top
down BOM. Design BOM is usually CAD driven with physical and geometric aspect
is modeled in CAD software and related data manages in PLM which is usually
integrated with CAD package. Design BOM evaluate from basic CAD design to sophisticated
CAE for Analysis BOM. Typically CAE BOM is derived for detail design BOM and is
cross link through BOM management software. Once Design BOM is release for
multiple iterative process and analysis, it handed over to manufacturing
department for manufacturing the product from Design BOM. Manufacturing again
realign the BOM from manufacturing aspect and create MBOM.

Manufacturing BOM:

Manufacturing engineer create MBOM (Manufacturing BOM) from
Design BOM. The basic difference between Design BOM and MBOM is that design
engineer look the Product in development from perspective of end product with
detail of parts and components where manufacturing engineer look it from perspective
of manufacturability of the product. Hence manufacturing view of BOM component
and there sequence might be different from that of designer. For example
designer might look two components for the given assembly as direct child of
assembly, where as manufacturing might look same two components as parent child
of each other from assembly sequence perspective. Similarly same component in
the design BOM might be shown as two parts in manufacturing BOM. For example T plate
might be single part for the designer but for manufacture engineer it two parts
with welding operation. Apart from component reorientation manufacture engineer
also add information in MBOM related to tools, fixture etc to encapsulate
complete information for manufacturing the product. MBOM can be either created
in PLM system or ERP like SAP PP. MBOM is usually required CAD assistance for
aligning the design part and adding resource like tools and fixtures. Also most
of manufacturing are done through NC (Numeric Control) machine, hence NC programming
is also create from the given geometry information of part in MBOM. This NC
programming is feed in to machine through series of operation information also
called routing or Bill of Process. Routing or BOP (Bill of Process) is a detail
operation sequence to produce or assemble a given Part or Product. The BOP is
created in context of Manufacturing BOM and BOM component can be related to one
or more operation in BOP. Rout

ing or BOP is usually done in ERP like SAP, but
now PLM vendor also provide very good functionality for Routing which tightly
integrate by MBOM and CAD\CAM and NC. Teamcenter provide Part Planer which
provide tight integration with MBOM, BOP and NX CAM. This type integration provides
better leveraging of information in one place. The below diagram depicit the complete lifecycle of BOM and relation between MBOM and Bill of Process.

Service BOM:

Once Part or Product is manufactured, it required to be service
and maintained throughout Product life cycle. For consumer items like Mobile,
TV etc it means managing serviceable parts and for complex product for example
heavy machinery it means not only managing serviceable parts inventory, but
also managing periodic maintenance and overhaul of the system. Hence OEM
(Original Equipment Manufacturer) also publish Service Bill of Material along
with Product specification, so that proper planning for spare part inventory, maintenance
and overhaul can be done by Product owner. Service BOM usually will be derived
from Design BOM as it’s more closely related to part information and detail
then the manufacturing. But it also will derive from MBOM from maintenance and
overhaul perspective. For example assembly sequence. Service BOM also contains more specific
information relevant to serviceability perspective like information of oil on
bearing etc.

That’s all on BOM Lifecycle. Hope this might help you to
understand overall Bill of Material concept and its use in various stage of
Product.